Antimetastatic Potential in Mice after Gene Therapy with Plasmid AMEP

Gene electrotransfer of Plasmid AMEP is a new antiangiogenic approach in cancer treatment. While the local effects after intratumoral administration have been already studied, systemic effects still need to be elucidated. Therefore intramtumoral or intramuscular gene therapy with Plasmid AMEP was performed and effects on distant tumors or metastases were observed and compared. Only 8% of the mice developed distant metastases after Plasmid AMEP gene electrotransfer, compared to 40% in the control groups. Additionally, intramuscular gene elctrotransfer performed before the tumor implantation, has no effect on the tumor outgrowth regardless of the GET protocol used. Study showed that gene therapy with Plasmid AMEP has antimetastatic potential only after intratumoral, but not after intramuscular gene electrotransfer. Most probably circulating AMEP peptide produced in muscle cells may be rapidly biodegraded and could not be able to reach tumor site in high amounts needed for AMEP effectiveness.